How to Make a Sodium Hydroxide Solution

By adding Na2CO3(aq) to Ca(OH)2(aq) you can make a dilute solution of sodium hydroxide.

Category:

Science & Technology

Tags:

• NaOH
• Ca(OH)2
• Na2CO3
• Chemistry

[Lorentz5]

Calcium hydroxide solubility in water is 0.189 g/100 mL, so how the heck are you getting it to react with the sodium carbonate? Don't both reactants need to be dissolved in order to react? I tried to do a larger scale of this (37g Ca(OH)2 with 53g Na2CO3), evaporated the filtrate, and all I got was a bunch of unreacted sodium carbonate (which is also basic and would produce the same effect on your paper).

[AHW214]

@Lorentz5

I got this experiment from a kit. According to the reaction NaOH is produced. How much water did you use in the reaction. Maybe using more water to dissolve all the chemicals could help react all the Ca(OH)2 and Na2CO3.

[mikeysgame]

why would you want to do this, sodium hydroxide is much cheaper and MUCH eiser to come by than calcum hydroxide if you realy need sodium hydroxide, might i suggest you buy it.

[AHW214]

@mikeysgame

I'm doing this for the science.

[jbohbot1]

here is what is actiually happening in the chemistry (i think):

you are reacting two chemicals (Na2CO3 and CaOH) to make CaCO3 and 2NaOH. CaCO3 is insoluble in water therefore comes out of the reaction as a percipitate and does not go through the filter paper. anyone wants to add anything to my explanation?

[AHW214]

@jbohbot1

I'm pretty sure that's right. Here's an equation:

Na2CO3+Ca(OH)2=2NaOH+CaCO3

[ChemExperimentalist]

@AHW214 I was thinking about replacement of the Na2CO3 by a baking soda NaHCO3 and instead of calcium hydroxide, i would use copper hydroxide. Is the equation right ? 2NaHCO3+Cu(OH)2 --> 2NaOH+CuCO3+CO2+H2O

[sk8rcreator]

omg is thtchem c 3000 science kit if so tell me if it's 3000 or 2000

[98JMA]

@AHW214

All you really need is dilute solutions of both chemicals. As long as all of the reactants are dissolved initially, the only solid you'll get is the precipitate of insoluble calcium carbonate which can then be filtered off.

[Thedude321ful]

mad it should work with byproducts so u filtered it cool ur a genius! but its much cheaper to buy it. i no this is only to explore science, so its pretty good :)

[Me102288]

just got a 5 pound container of crystalized koh for $20 at the hardware store.

Use it for electrolyte in my hydrogen reactor :-)

[Me102288]

just got a 5 pound container of crystalized koh for $20 at the hardware store.

Use it for electrolyte is my hydrogen reactor :-)

[98JMA]

@AHW214

To be posh, a double-decomposition reaction is observed between the Sodium Carbonate and Calcium Hydroxide, and, yes, because of it's insolubilty in water at RTP, the Calcium Carbonate by-product precipitates out leaving the NaOH in solution.

[labmaster49]

@mikeysgame sodium Hydroxide can also be hard to find, depending where you live

[petrus4]

Great video, but I admit to preferring the ones with crazed survivalist rednecks trying to make lye with animal fat and a campfire. They're far more entertaining. ;)